The gas turbine includes a rotor that rotates around an axial line, and a casing that covers the rotor. The rotor includes a rotor shaft and a plurality of blades that are attached to the rotor shaft. Furthermore, a plurality of vanes are attached to the inner circumferential side of the casing. The blade includes a blade body with an airfoil shape, a platform that extends in essentially a perpendicular direction with respect to the blade height direction from an end portion in the blade height direction of the blade body, and a shaft attachment portion that extends from the platform to the opposite side as the blade body.
The blades and vanes of the gas turbine are exposed to high temperature combustion gas. Therefore, the blades and vanes are generally cooled by air or the like.
For example, various types of cooling channels through which cooling airflow are formed in the rotating blade described in the following Patent Document 1. Specifically, blade channels where cooling air flows, with an interior that extends in the blade height direction are formed in the blade body, platform, and shaft attachment part. A gas path surface facing in the blade height direction and that contacts the combustion gas, a reverse gas path surface with a back matching relationship to the gas path surface, and an end surface along an edge of the gas path surface are formed in the platform. Furthermore, a platform channel where cooling gas flows is formed in the platform. The platform channel is a serpentine channel. The serpentine channel has a plurality of channels extending in a specific direction and arranged in a perpendicular direction to the specific direction. The serpentine channel forms a channel where ends of a plurality of channels are mutually connected to form an overall zigzag channel.